Cutting tools and cutting inserts including internal cooling

ABSTRACT

A cutting tool comprises a cutting insert, a tool holder, and a fastener. The cutting insert comprises a cutting edge and a fastener bore adapted to accept a fastener for fastening together the cutting tool and tool holder. A coolant flow recess in the fastener bore is adapted to direct coolant though the coolant flow recess and toward a head portion of the fastener. The tool holder comprises an insert pocket adapted to removably fasten the cutting insert and fastener to the tool holder, and a coolant bore adapted to direct the coolant from the tool holder to the coolant flow recess of the fastener bore. The head portion of the fastener and the coolant flow recess of the fastener bore define a gap that directs the coolant to the cutting edge of the cutting insert.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application claiming priority under35 U.S.C. § 120 to U.S. patent application Ser. No. 12/900,544, entitledCUTTING TOOLS AND CUTTING INSTRUMENTS INCLUDING INTERNAL COOLING, filedon Oct. 8, 2010, the entire disclosure of which is hereby incorporatedby reference herein.

BACKGROUND OF THE TECHNOLOGY

1. Field of the Technology

The present disclosure relates to cutting tools and cutting inserts formachining metallic materials.

2. Description of the Background of the Technology

As used herein, the term “metal cutting” broadly refers to machining,turning, milling, drilling, boring, planing, shaping, reaming, and likematerial removal operations performed on metallic (i.e., metal and metalalloy) materials. Cutting tools used in metal cutting typically aresubjected to high loads and high temperatures. During metal cutting, thecutting tool applies a high load to the metallic workpiece to deform theworkpiece. Because of the relative motion of the workpiece and thecutting edge of the cutting tool, shear deformation is produced in themetallic workpiece, generating metal chips from the workpiece. A cuttingtool tip or cutting insert will generally include a rake face, which isa portion of the tip or insert that encounters and further deforms chipsafter the chips are formed at the cutting edge of the tip or insert.Cutting inserts may also include additional features that control chipsize and shape. The chips produced in metal cutting are hot fromdeformation and frictional forces and are in close contact for a timewith the cutting tip or cutting insert.

Because cutting inserts experience high loads and frictional contactwith the workpiece and the machined chips, the cutting insert, andparticularly the insert's cutting edge, is heated to very hightemperatures. For example, cemented carbide cutting inserts may beheated to temperatures greater than 1,800° F. (982° C.) during cuttingof hard steels. High cutting insert temperatures increase wear duringmetal cutting and, thus, reduce cutting insert service life. Machinetool operators can reduce tool speed to at least partially counteracthigh temperature-induced cutting insert wear. Reducing tool speed,however, may adversely affect the finish quality of machined surfacesproduced on a metallic workpiece. Instead, a coolant is typically usedto cool the cutting edge of a cutting insert during metal cutting.

Metal cutting coolants, which are also referred to as cutting fluids,serve to lubricate the workpiece and reduce frictional forces at lowcutting speeds. At higher cutting speeds, coolants predominantly act tocool the workpiece and the cutting insert, and assist in flushing chipsaway from the cutting insert. The use of coolants in metal cuttingsignificantly increases cutting insert service life, reduces unintendeddeformation of the workpiece, improves surface finish quality, andenhances chip removal and handling.

Traditionally, coolants are fed from an external source to the region ofthe interface between the cutting edge of a cutting insert and theworkpiece. For example, a flow of coolant may be flooded onto both theworkpiece and cutting insert through tubing from an external coolantsource. Another method of applying coolant to the cutting edge/workpieceinterface region is to direct a jet of coolant at the interface region.Still another method of applying coolant involves misting a coolant withan air jet and directing the mist at the cutting edge/workpieceinterface region.

Conventional methods of applying coolants to a cutting edge/workpieceinterface region are inefficient. For example, an excess amount ofexpensive coolant typically is applied during metal cutting to betterensure that coolant will contact the interface region and remove heatfrom the cutting insert's cutting edge. However, although excess coolantis applied, because of the tight tolerances at the interface region andthe continuous generation of chips at the interface, less than anoptimal amount of coolant is delivered to the interface region toefficiently and effectively reduce the temperature of the cuttinginsert's cutting edge. As such, the operating temperature of the cuttinginsert's cutting edge may remain very high, reducing cutting insertservice life.

Accordingly, a need exists for an improved arrangement for reducing thetemperature of the cutting edge of a metal cutting insert during cuttingoperations. In particular, a need exists for an improved system todeliver coolant to the cutting edge/workpiece interface during cuttingoperations.

SUMMARY

An aspect according to the present disclosure is directed to a cuttinginsert comprising at least one cutting edge and at least one fastenerbore adapted to accept a fastener for removably securing the cuttinginsert to a tool holder. The fastener bore includes at least one coolantflow recess adapted to direct a coolant though the coolant flow recessand toward the at least one cutting edge when the cutting insert issecured to the tool holder by a fastener.

An additional aspect according to the present disclosure is directed toa cutting tool comprising a cutting insert, a tool holder, and afastener. The cutting insert comprises at least one cutting edge and atleast one fastener bore adapted to accept a fastener for removablysecuring the cutting insert to the tool holder. The at least onefastener bore includes at least one coolant flow recess adapted todirect a coolant though the coolant flow recess and toward a headportion of the fastener when the cutting insert is secured to the toolholder by the fastener. The tool holder comprises at least one insertpocket adapted to accept the cutting insert and allow the cutting insertto be secured to the tool holder by the fastener. The tool holderfurther comprises at least one coolant bore adapted to direct coolantfrom the tool holder to the at least one coolant flow recess of thefastener bore. The head portion of the fastener and the coolant flowrecess of the fastener bore define a gap that directs coolant toward thecutting edge of the cutting insert.

An additional aspect according to the present disclosure is directed toa cutting insert including an internal coolant system, wherein thecutting insert comprises at least one cutting edge, at least onefastener bore adapted to accept a fastener for removably fastening thecutting insert to a tool holder, and at least one through cavitypositioned adjacent to the fastener bore. The at least one throughcavity extends from a top face of the cutting insert to a bottom face ofthe cutting insert and is adapted to direct a coolant fluid though thecutting insert and toward the at least one cutting edge when the cuttinginsert is fastened to a tool holder by a fastener.

Yet an additional aspect according to the present disclosure is directedto a cutting tool comprising a cutting insert, a tool holder, and afastener. The cutting insert comprises at least one cutting edge, atleast one fastener bore adapted to accept a fastener for removablyfastening the cutting insert to the tool holder, and at least onethrough cavity adapted to direct a coolant though the cutting insert andtoward a head portion of the fastener when the cutting insert isfastened to the tool holder by the fastener. The tool holder comprisesat least one coolant bore adapted to direct a coolant from the toolholder to the at least one through cavity of the cutting insert. Thehead portion of the fastener and the at least one through cavity of thecutting insert define a gap that directs coolant to the at least onecutting edge of the cutting insert.

BRIEF DESCRIPTION OF THE DRAWINGS

The features and advantages of methods described herein may be betterunderstood by reference to the accompanying drawings in which:

FIG. 1( a) is a schematic top view of a non-limiting embodiment of adouble-sided milling cutting insert according to the present disclosureincluding four coolant flow recesses;

FIG. 1( b) is a schematic top view of a non-limiting embodiment of thedouble-sided milling cutting insert of FIG. 1( a) and a fasteneraccording to the present disclosure;

FIG. 1( c) is a schematic cross-section of a non-limiting embodiment ofa cutting insert, a fastener, and a portion of a tool holder accordingto the present disclosure, revealing coolant flow recesses in thefastener bore of the cutting insert and coolant flow guided by a headportion of the fastener;

FIGS. 2( a) and 2(b) are a schematic side view and a schematic end view,respectively, of a non-limiting embodiment of a cutting (milling) toolaccording to the present disclosure, showing multiple cutting insertssecured in the holder of the cutting tool with multiple fasteners;

FIG. 3( a) is a schematic top view of a non-limiting embodiment of adouble-sided milling cutting insert according to the present disclosureincluding three coolant flow recesses;

FIG. 3( b) is a schematic top view of the double-sided milling cuttinginsert of FIG. 3( a) and a fastener according to the present disclosure;

FIG. 3( c) is a schematic cross-section of a non-limiting embodiment ofa cutting insert, a fastener, revealing coolant flow recesses in thefastener bore of the cutting insert and coolant flow guided by a headportion of the fastener;

FIG. 4( a) is a schematic top view of a non-limiting embodiment of adouble-sided milling cutting insert according to the present disclosure,including three coolant flow recesses, and including multiple coolantflow recess segments;

FIG. 4( b) is a schematic top view of the double-sided milling cuttinginsert of FIG. 4( a) and a fastener according to the present disclosure;

FIG. 4( c) is a schematic cross-section of a non-limiting embodiment ofa cutting insert, and a fastener, revealing coolant flow recesses in thefastener bore of the cutting insert and coolant flow guided by a headportion;

FIG. 5( a) is a schematic top view of a non-limiting embodiment of asingle-sided milling cutting insert according to the present disclosureincluding four coolant flow recesses;

FIG. 5( b) is a schematic top view of the single-sided milling cuttinginsert of FIG. 5( a) and a fastener according to the present disclosure;

FIG. 5( c) is a schematic cross-section of a non-limiting embodiment ofa cutting insert, and a fastener, revealing coolant flow recesses in thefastener bore of the cutting insert and coolant flow guided by a headportion;

FIG. 6( a) is a schematic top view of a non-limiting embodiment of asingle-sided cutting insert for boring operations according to thepresent disclosure including four coolant flow recesses;

FIG. 6( b) is a schematic top view of the single-sided cutting insert ofFIG. 6( a) and a fastener according to the present disclosure;

FIG. 6( c) is a schematic folded section of a non-limiting embodiment ofa cutting insert for boring operations, and a fastener, revealingcoolant flow recesses in the fastener bore of the cutting insert andcoolant flow guided by a head portion of the fastener;

FIGS. 7( a) through 7(d) are schematic representations of a cutting toolsystem comprising a boring tool holder, a boring cutting insert, and afastener according to FIGS. 6( a) through 6(c);

FIG. 8( a) is a schematic top view of a non-limiting embodiment of adouble-sided turning cutting insert for turning operations according tothe present disclosure including four coolant flow recesses;

FIG. 8( b) is a schematic top view of a non-limiting embodiment of thedouble-sided turning cutting insert of FIG. 8( a) and a fasteneraccording to the present disclosure;

FIG. 8( c) is a schematic folded section of a non-limiting embodiment ofa cutting insert for turning operations, and a fastener, revealingcoolant flow recesses in the fastener bore of the cutting insert andcoolant flow guided by a head portion of the fastener;

FIGS. 9( a) through 9(d) are schematic views of a non-limitingembodiment of a cutting tool system comprising a turning tool holder, aturning cutting insert, and a fastener according to FIGS. 8( a) through8(c);

FIG. 10( a) is a schematic top view of a non-limiting embodiment of adouble-sided drilling cutting insert for drilling operations accordingto the present disclosure including four coolant flow recesses;

FIG. 10( b) is a schematic top view of the double-sided drilling cuttinginsert for drilling operations of FIG. 10( a) and a fastener accordingto the present disclosure;

FIG. 10( c) is a schematic folded section of a non-limiting embodimentof a cutting insert for drilling operations, and a fastener, revealingcoolant flow recesses in the fastener bore of the cutting insert andcoolant flow guided by a head portion of the fastener;

FIGS. 11( a) through 11(d) are schematic views of a non-limitingembodiment of an internal coolant system according to the presentdisclosure adapted for general machining operations;

FIG. 12( a) is a schematic top view of a non-limiting embodiment of acutting insert according to the present disclosure adapted for generalmachining operations and including four through cavities;

FIG. 12( b) is a schematic top view of the cutting insert of FIG. 12( a)and a fastener according to the present disclosure; and

FIG. 12( c) is a schematic folded section of a non-limiting embodimentof a cutting insert for general machining operations, a fastener, and aportion of a tool holder according to the present disclosure, revealingthrough cavities in the cutting insert and coolant flow guided by a headportion of the fastener.

The reader will appreciate the foregoing details, as well as others,upon considering the following detailed description of certainnon-limiting embodiments of cutting tools, tool holders, and cuttinginserts according to the present disclosure.

DETAILED DESCRIPTION OF CERTAIN NON-LIMITING EMBODIMENTS

In the present description of non-limiting embodiments, other than inthe operating examples or where otherwise indicated, all numbersexpressing quantities or characteristics are to be understood as beingmodified in all instances by the term “about”. Accordingly, unlessindicated to the contrary, any numerical parameters set forth in thefollowing description are approximations that may vary depending on thedesired properties one seeks to obtain in the cutting tools, toolholders, and cutting inserts according to the present disclosure. At thevery least, and not as an attempt to limit the application of thedoctrine of equivalents to the scope of the claims, each numericalparameter should at least be construed in light of the number ofreported significant digits and by applying ordinary roundingtechniques.

Any patent, publication, or other disclosure material that is said to beincorporated, in whole or in part, by reference herein is incorporatedherein only to the extent that the incorporated material does notconflict with existing definitions, statements, or other disclosurematerial set forth in the present disclosure. As such, and to the extentnecessary, the disclosure as set forth herein supersedes any conflictingmaterial incorporated herein by reference. Any material, or portionthereof, that is said to be incorporated by reference herein, but whichconflicts with existing definitions, statements, or other disclosurematerial set forth herein is only incorporated to the extent that noconflict arises between that incorporated material and the existingdisclosure material.

A non-limiting aspect according to the present disclosure is directed toan improved cutting insert that is adapted to internally channel,divert, and/or direct a coolant (i.e., a cutting fluid) through thecutting insert and toward a cutting edge of the cutting insert. Byinternally directing coolant to the cutting edge, the ability to removeheat from the cutting edge is improved. The improvement in removing heatfrom the cutting edge made possible by the present invention reduces thequantity of coolant needed during metal cutting, may allow for increasedcutting speeds, reduces frictional heating, and increases the servicelife of cutting inserts.

FIG. 1( a) is a schematic top view of a non-limiting embodiment of adouble-sided milling cutting insert 10 according to the presentdisclosure including four coolant flow recess 11 provided by removingmaterial from a wall of the fastener bore 12 of the cutting insert 10.The center point of the fastener bore 12 is identified as point “0”.FIG. 1( b) is a schematic top view of the double-sided milling cuttinginsert 10 shown in FIG. 1( a) and with a fastener 13 disposed in thefastener bore 12 of the cutting insert to secure the cutting insert 10on a milling tool holder (not shown in FIG. 1( b)). FIG. 1( c) is asectional view taken at line E-E in FIG. 1( b) (center line 14), whichpasses along the longitudinal axis of fastener 13, showing the cuttinginsert 10 on a milling tool holder 15 including internal coolant bore16. The flow of coolant is depicted by the series of arrows 17. Thecoolant flow 17 passes through the tool holder 15, and emerges fromcoolant bore 16, passes through the cutting insert 10, and is guided bythe head portion 19 of the fastener 13 towards the cutting edge 20 ofthe cutting insert 10 that is positioned to contact a workpiece duringthe milling operation.

As can be seen from FIGS. 1( a) through 1(c), cutting insert 10comprises at least one fastener bore 12 adapted to accept a fastener 13.The fastener 13 removably secures the cutting insert 10 to tool holder15. Fastener bore 12 comprises a plurality of coolant flow recesses 11in the fastener bore 12, extending axially along the fastener bore 12.The coolant flow recesses 11 are adapted to direct a coolant along thecoolant flow recesses 11 and the fastener 13 and toward at least onecutting edge 20 of the cutting insert 10 when the cutting insert 10 issecured to a tool holder by a fastener 13 disposed through the fastenerbore 12.

The coolant flow recesses 11 may be formed by cutting or otherwiseremoving material from the original wall or surface 23 of the fastenerbore 12. Alternatively, the coolant flow recesses 11 may be built intothe tooling dies and created when the cutting insert 10 is pressed in amold or extruded in an injection machine. The coolant flow recesses 11extend from the top face 21 of the cutting insert 10 to the bottom face22 of the cutting insert 10. The fastener 13 is in physical contact withthe cutting insert 10 at the remaining regions of the fastener boresurface 23 and secures the cutting insert 10 to the tool holder 15. Innon-limiting embodiments, the cutting insert 10 includes a chamfer 24(see detail portion of FIG. 1( c)) at the top face 21 and/or at thebottom face 22. In non-limiting embodiments, the profile 25 of a coolantflow recess 11 may be of any geometry, including, but not limited to aportion of circle, a portion of an ellipse, a line, a curve, a spline, apolygon, or any combination of these geometries.

As shown in FIG. 1( c), the fastener 13 serves a function in addition tosecuring the cutting insert 10 in the fastener bore 12 and to the toolholder 15. In particular, the fastener 13 guides or directs the coolantflow 17 to the active cutting edge 20 in action. As used herein, acutting edge that is “active” is oriented on a tool holder so that thecutting edge contacts a workpiece during machining operations. Againreferring to the detail portion of FIG. 1( c), a bottom face 26 of thehead portion 19 and the top edge 28 of the fastener bore 12 define aperipheral gap 29. Coolant flows through the gap 29 and is directedtowards the active cutting edge 20. The peripheral gap 29 functions as acoolant outlet that is defined between the bottom face 26 of the headportion 19 and the top portion of the fastener bore 12, including thetop edge 28 and chamfer 24.

The peripheral gap 29 may be specifically shaped to account for the typeand configuration of the cutting insert 10. For example, the bottom face26 of the head portion 19 may be parallel to a flat plateau 27 on thetop face 21 of a cutting insert. Such a design is advantageous if thecutting edge of the cutting insert and the top edge of the fastener boreare at about the same level (when the cutting insert is in anorientation as shown in FIG. 1( c)). Alternatively, for example, thebottom face 26 of the head portion 19 may be angled downwardly withrespect to a flat plateau 27 on the top face 21 of a cutting insert indesigns wherein the cutting edge is below the top edge of the fastenerbore (when the cutting insert is in an orientation as shown in FIG. 1(c)). According to another alternative, for example, the bottom face 26of the head portion 19 may be angled upwardly with respect to a flatplateau 27 on the top face 21 of the cutting insert in designs whereinthe cutting edge is generally above the top edge of the fastener bore,which is the specific design shown in the non-limiting embodiment ofFIG. 1( c).

As described hereinabove and shown in FIGS. 1( a) through 1(c), in anon-limiting embodiment of the present disclosure, an internal coolantsystem for cutting inserts comprises a cutting insert 10, a fastener 13,and a tool holder 15. The wall of the fastener bore 12 is partially cutout to form multiple coolant flow recesses 11. A bottom face 26 of thehead portion 19 of the fastener 13 has a predetermined geometricalrelationship with the top edge 28 and chamfer 24 of the fastener bore 12when the fastener 13 is positioned to secure the cutting insert 10 inthe fastener bore 12 and tool holder 15, thereby providing a gap 29. Acoolant flow recess 11 and a gap 29 provide a channel for coolant toflow from one or more internal coolant bores 16 in the tool holder 15 tothe interface between the fastener bore 12 and the fastener 13. Thebottom face 26 of the head portion 19 may be specifically designed toaccount for the type and configuration of the cutting insert 10 tothereby specifically direct the coolant flow 17 to the active cuttingedge 20 along the shortest possible distance. The non-limitingembodiments of internal coolant systems for cutting inserts describedherein are unique, yet simple in design, effective, and economical. Thefastener 13 provides the dual functions of (i) securing the cuttinginsert 10 to the tool holder 15; and (ii) guiding, channeling, and/ordirecting coolant precisely toward the active cutting edge 20.

In the non-limiting embodiment of a cutting insert depicted as cuttinginsert 10 in FIGS. 1( a) through 1(c), the cutting insert 10 includesfour cutting edges 20. However, it is within the scope of the presentdisclosure to provide a cutting insert 10 having any number of cuttingedges 20 (for example, a round insert with a single cutting edge, orcutting inserts with three, five, or more cutting edges) with theimproved coolant delivery features described herein. Further, in thenon-limiting embodiment depicted in FIGS. 1( a) through 1(c), the atleast one fastener bore 12 is centrally positioned on a side of cuttinginsert 10. However, it is within the scope of the present disclosurethat the fastener bore is not centrally positioned, but rather is in anyother suitable position on the cutting insert and/or that the cuttinginsert may include more than one fastener bore. In a non-limitingembodiment, the fastener 13 is threadedly received in the tool holder15.

Optionally, the cutting insert 10, along with other embodiments ofcutting inserts according to the present disclosure, may comprise one ormore rake faces and chip control features, and any other cutting insertfeatures known to a person having ordinary skill in the art. Suchfeatures are conventional and are known to those having ordinary skillin the art. Thus, they are not further discussed herein.

Cutting insert 10 may be made from any material suitable for the cuttingoperations for which the insert 10 is intended. In certain non-limitingembodiments, the cutting insert 10, along with other embodiments ofcutting inserts according to the present disclosure, is manufacturedfrom one or more materials selected from high speed steel, cobaltalloys, cemented carbides, cermets, ceramics, diamond, andpolycrystalline diamond. In various embodiments of cutting insertsaccording to the present disclosure, the cutting inserts comprise anymaterial known to a person skilled in the art that is used now orhereinafter for the manufacture of cutting inserts.

In certain non-limiting embodiments, the cutting insert 10, along withother embodiments of cutting inserts according to the presentdisclosure, comprises a wear coating, which may be a wear coatingcomposed of single or multiple layers. Examples of non-limitingembodiments of possible wear coatings include one or more of titaniumnitride, titanium carbide, aluminum oxide, silicon nitride, andzirconium oxide. In various embodiments of cutting inserts according tothe present disclosure, the cutting inserts include coatings of anysuitable materials known to a person skilled in the art that is used nowor hereinafter for wear coatings on cutting inserts.

According to a non-limiting aspect of the present disclosure, a cuttingtool including an internal coolant system comprises: a cutting insertincluding at least one internal coolant flow recess adapted to channel,divert, and/or direct a coolant (i.e., a cutting fluid) toward at leastone active cutting edge of the cutting insert; a tool body adapted topass coolant through the tool body and into at least one of the internalcoolant flow recesses of the cutting insert, and then on to or towardsat least one active cutting edge of the cutting insert. By internallydirecting coolant to the cutting edge, smaller quantities of coolant arerequired for metal cutting, cutting speeds may be increased, andfrictional heating is reduced, resulting in longer cutting insert life.

FIG. 2( a) depicts a side view of a non-limiting embodiment of a cuttingtool 40 according to the present disclosure, and FIG. 2( b) depicts afront-end view of the cutting tool 40. The cutting tool 40 comprises: amilling tool holder 41 including a coolant delivery system that issubstantially similar in design to the system shown in FIG. 1( c); fiveindexable cutting inserts 42 a through 42 e, which are substantiallysimilar in design to the cutting insert 10 described above and shown inFIGS. 1( a) through 1(c); and five fasteners 43 a through 43 e, whichare substantially similar in design to fastener 13 described above andshown in FIGS. 1( b) and 1(c). In a non-limiting embodiment thefasteners 43 a through 43 e are threadedly received in the tool holder41.

FIGS. 3( a) through 3(c) illustrate another non-limiting embodiment of adouble-sided milling cutting insert 50 including an internal coolantsystem according to the present disclosure. FIG. 3( a) depicts a topview of the cutting insert 50 including three coolant flow recesses 51formed along a wall of the fastener bore 52. FIG. 3( b) depicts a topview of the cutting insert 50 and further depicts a fastener 53 disposedin the fastener bore 52. FIG. 3( c) depicts a sectioned view of cuttinginsert 50 and fastener 52 taken along line P-P (also identified as line54) in FIG. 3( b). The sectioned view of FIG. 3( c) illustrates coolantflow 55 from the tool holder (not shown) and through the coolant passagechannel 56 defined between a coolant flow recess 51 of the cuttinginsert 50 and the fastener 53. A peripheral gap 61 that serves as acoolant outlet is defined between the top portion 62 of the fastenerbore 52 and the bottom face 63 of the head portion 64 of the fastener53. The bottom face 63 is specifically shaped to account for the typeand configuration of the cutting insert 50 and thereby direct thecoolant flow 55 precisely toward the cutting edge 65.

FIGS. 4( a) through 4(c) depict another non-limiting embodiment of adouble-sided milling cutting insert including an internal coolant systemaccording to the present disclosure. FIG. 4( a) depicts a top view ofthe cutting insert 70, which includes three coolant flow recesses 71defined along a wall of the fastener bore 72. FIG. 4( b) depicts a topview of cutting insert 70 and further depicts a fastener 73 disposed inthe fastener bore 72. FIG. 4( c) is a sectional view of the cuttinginsert 70 and fastener 73 taken along line R-R (also identified as line75) in FIG. 4( b). The cutting insert 70 is similar to the cuttinginsert 50 shown in FIGS. 3( a) through 3(c), but, as shown in FIG. 4(c), each coolant flow recess 71 of cutting insert 70 comprises multiplesegments 71 a, 71 b and 71 c. In the embodiment shown in FIG. 4( c),segment 71 a forms an angle of less than 90° with the axis 77 of thefastener 73, segment 71 b is substantially parallel to the axis 77 ofthe fastener 73, and segment 71 c also forms an angle of less than 90°with the axis 77 of the fastener 73. FIG. 4( c) also indicates coolantflow 78 through the cutting insert 70, which is directed toward acutting edge of the cutting insert 70 by a gap defined between a headportion of the fastener 73 and the cutting insert 70.

FIGS. 5( a) through 5(c) illustrate a non-limiting embodiment of asingle-sided milling cutting insert including an internal coolant systemaccording to the present disclosure. FIG. 5( a) is a top view of thecutting insert 80 including four recesses 81 along the wall of thefastener bore 82. FIG. 5( b) is a top view of the cutting insert 80 andfurther depicts a fastener 83 disposed in the fastener bore 82. FIG. 5(c) is a sectional view of the cutting insert 80 and fastener 83 takenalong line A-A (also identified as line 85) in FIG. 5( b). As shown inthe detail section of FIG. 5( c), a peripheral gap 91 that functions asa coolant outlet is defined between a top portion 92 of the fastenerbore 82 and the bottom face 93 of the head portion 94 of the fastener83. The bottom face 93 is specifically shaped to interact with the topportion 92 of the fastener bore 82 and direct coolant flow 95 preciselytowards cutting edge 96.

FIGS. 6( a) through 6(c) illustrate a non-limiting embodiment of asingle-sided boring cutting insert including an internal coolant systemaccording to the present disclosure. FIG. 6( a) depicts a top view ofthe cutting insert 100 including four coolant flow recesses 101 alongthe wall of the fastener bore 102. FIG. 6( b) is a top view of thecutting insert 100 and further depicts a fastener 103 disposed in thefastener bore 102. FIG. 6( c) is a sectional view taken along B-B inFIG. 6( b) (i.e., the folded section line 105), which passes through acoolant flow recess 101 at point N1, changes direction at the centerpoint of the cutting insert 100, and passes though the original fastenerbore periphery 106 at point N2 (see FIG. 6( a)). A peripheral gap 111that functions as a coolant outlet is defined between a top portion 112of fastener bore 102 and a bottom face 113 of a head portion 114 of thefastener 103. The bottom face 113 is specifically shaped so that thecoolant flow 115 is directed precisely towards the active cutting edge116.

FIGS. 7( a) through 7(d) depict a non-limiting embodiment of a boringtool according to the present disclosure, wherein the boring tool 120comprises a boring tool holder 121, a boring cutting insert 100 aspresented in FIGS. 6( a) through 6(c), and a fastener 103 as shown inFIGS. 6( b) and 6(c). FIG. 7( a) is a perspective view of a working endof the cutting tool 120, with coolant flow 125 emerging between thefastener 103 and the cutting insert 100. FIG. 7( b) is a top view of aworking end of the cutting tool 120 with coolant flow 125 emerging frombetween the fastener 103 and the cutting insert 100. FIG. 7( c) is a topview of the tool holder 121 (with the cutting insert 100 and thefastener 103 removed) showing internal coolant bores 122, 123, and 124formed in the tool holder 121. FIG. 7( d) is a top view of the toolholder 121 and the cutting insert 100 showing the positionalrelationship between a coolant flow recess 101 and the fastener bore122. As indicated in FIG. 7( c), coolant passes through bore 124 alongthe length of the tool holder 121, passes into bore 123, and emergesfrom bore 122 positioned on a surface of the insert pocket of the toolholder 121. As indicated in FIGS. 7( a), 7(b), and 7(d), coolantemerging from bore 122 passes through the interior of cutting insert 100and emerges from a gap defined between the cutting insert 120 and thefastener 103 as coolant flow 125. In this way, coolant may be fedaxially through the tool holder 121, introduced into the interior of thecutting insert 100, and directed towards a cutting edge of the cuttinginsert 100.

FIGS. 8( a) through 8(c) illustrate a non-limiting embodiment of aturning cutting insert 130 including an internal coolant systemaccording to the present disclosure. FIG. 8( a) is a top view of thecutting insert 130 including four coolant flow recesses 131 formed alongthe wall of the fastener bore 132. FIG. 8( b) is a top view of cuttinginsert 130 and further depicts a fastener 133 disposed in the fastenerbore 132. FIG. 8( c) is a sectional view taken along C-C in FIG. 8( b)(i.e., the folded section line 135), which passes through a coolant flowrecess 131 at point M2, changes direction at the center point of thecutting insert 130, and passes though the original fastener boreperiphery 134 at point M1 (see FIG. 8( a)). As shown in the detailsection of FIG. 8( c), a peripheral gap 141 that functions as a coolantoutlet is defined between the top portion 142 of the fastener bore 132and the bottom face 143 of the head portion 144 of fastener 133. Thebottom face 143 is specifically shaped to account for the type andconfiguration of the cutting insert 130 and direct the coolant flow 145precisely towards the active cutting edge 146 of cutting insert 130.Contact between original fastener bore periphery 134 at M1 and thefastener 133 partially secures the fastener to an insert pocket of atool holder.

FIGS. 9( a) through 9(d) show a non-limiting embodiment of a cuttingtool according to the present disclosure. Turning tool 150 comprises aturning tool holder 151, a turning cutting insert 130 as described inFIGS. 8( a) through 8(c), and a fastener 133 as described in FIGS. 8( b)and 8(c). FIG. 9( a) is a perspective view of the cutting tool 150, andFIG. 9( b) is a top view of a working end of the cutting tool 150,wherein both figures show coolant flow 159 directed from a peripheralgap 141 that functions as a coolant outlet and is defined between thehead portion 144 of the fastener 133 and the cutting insert 130 (seeFIG. 8( c)). FIG. 9( c) is a top view of the tool holder 151, with thecutting insert 130 and the fastener 133 removed, showing internalcoolant bores 152, 153, 154, 155, and 156. FIG. 9( d) is a top viewshowing the tool holder 151 and the cutting insert 150 and indicatingthe positional relationship between one of the coolant flow recesses 131(see FIG. 8) and coolant bore 152 which is perpendicular to the pocketseat face 157. The ends of the internal coolant bores 153, 154 and 155may be blocked by set screws (not shown), to prevent flow of coolantfrom the bores.

FIGS. 10( a) through 10(c) illustrate another non-limiting embodiment ofa drilling cutting insert 160 including an internal coolant systemaccording to the present disclosure. FIG. 10( a) is a top view of thecutting insert 160 including four coolant flow recesses 161 along thewall of the fastener bore 162. FIG. 10( b) is a top view of cuttinginsert 160 and further depicts a fastener 163 disposed in the fastenerbore 162. FIG. 10( c) is a sectional view taken along H-H in FIG. 10( b)(i.e., the folded section line 165), which passes through a coolant flowrecess 161 at point L2, changes direction at the center point of thecutting insert 160, and passes though the original fastener boreperiphery 164 at point L1 (see FIG. 10( a)). As shown in the detailportion of FIG. 10( c), a peripheral gap 171 that functions as a coolantoutlet is defined between the top portion 172 of the fastener bore 162and the bottom face 173 of the head portion 174 of the fastener 163. Thebottom face 173 is specifically shaped to account for the type andconfiguration of the cutting insert 160 so that the coolant flow 175 isdirected precisely towards the active cutting edge 176.

Further, as shown in FIG. 10( a) and FIG. 10( c), each coolant flowrecess 161 comprises multiple segments 161 a and 161 b, wherein segment161 a defines an angle with the axis 177 of the fastener 163, whilesegment 161 b defines an angel in the opposite direction with the axis177 of the fastener 163.

FIGS. 11( a) through 11(d) show a non-limiting embodiment of a drillingtool 180 according to the present disclosure comprising a drilling toolholder 181, two drilling cutting inserts 182 and 183 (with the drillinginsert 182 as a peripheral insert and the drilling insert 183 as acenter insert), and two fasteners identical to fastener 163 shown inFIG. 10( c). The geometry and shape of the coolant flow recesses of bothdrilling cutting inserts 182 and 183 are the same as those of thedrilling cutting insert 160 described in regards to FIGS. 10( a) through10(c). Each of the drilling cutting inserts 182 and 183 are secured by afastener 163 threadedly received in a fastener bore in each cuttinginsert. FIG. 11( a) is a perspective view of the drilling tool 180, andFIG. 11( b) is a top view of the drilling tool 180. FIG. 11( c) is a topview of the tool holder 181 (wherein the pocket seat face 197 forseating the peripheral drilling insert 182 faces out of the page)showing internal coolant bores 190 through 196 passing through the toolholder 181 and exiting on the pocket seat faces. FIG. 11( d) is a bottomview of the tool holder 181 (wherein the pocket seat face 198 forseating the center drilling insert 183 faces out of the page) showinginternal coolant bores 190 through 196 passing through the tool holder181 and exiting on the pocket seat faces. As can been seen from FIG. 11(c) and FIG. 11( d), two coolant bores 195 and 196 (internally connectedby coolant bore 194 from the pocket seat 198 of the tool holder 181)exit on the pocket seat for the center drill insert 183 and, therefore,two coolant flows 186 and 187 are directed toward cutting edges of thecenter drill insert. Only one coolant bore 193 exits on pocket seat 197supporting the peripheral drill insert 182 and, therefore, only a singlecoolant flow 185 is directed to a cutting edge of the peripheral drillinsert. However, if desired, the tool holder 180 can be easily modifiedto provide coolant flows from two or more coolant outlets to theperipheral drill insert 182.

FIGS. 12( a) through 12(c) illustrate another non-limiting embodiment ofa cutting insert including an internal coolant system and adapted forgeneral machining operations according to this disclosure. FIG. 12( a)is a top view of cutting insert 210 including four through cavities 211extending from top face 214 to bottom face 216 of the cutting insert 210adjacent fastener bore 212. FIG. 12( b) is a top view of cutting insert210 including a fastener 213 through fastener bore 212. FIG. 12( c) is asectional view taken along V-V in FIG. 12( b) (i.e., the folded sectionline 215), which passes through a through cavity 211, changes directionat the center point of the cutting insert 210, and passes though asection of the cutting insert 210 that does not include a through cavity211. Further, each through cavity 211 includes a pair of side extrusions217 flanking each through cavity 211 on both top and bottom faces 214,216, and with function as side blocks to limit coolant flow 225. A gap221, which functions as a coolant outlet 221, is defined between the topportion 222 of a through cavity 211 and a bottom face 223 of a headportion 224 of the fastener 213. The bottom face 223 is specificallyshaped to account for the type and configuration of the cutting insert210 so that the coolant flow 225 is directed precisely towards an activecutting edge 226. Further, the side extrusions 217 on the cutting insert210 define a small gap with the bottom face 223 of the head portion 224once secured on a tool holder by the fastener 213. In certainnon-limiting embodiments, the through cavities 211 are drilled (in thecase of being a cylindrical hole) prior to furnace sintering the cuttinginsert 210. Alternatively, and without limitation, the through cavitiesmay be built into the tooling dies and created when the cutting insert210 is pressed in a mold or extruded in a powder injection machine. Thethrough cavities 211 may have any suitable geometry including, but notlimited to, a circle, an ellipse, lines, curve(s), spline(s), polygons,and combinations of any of those geometries.

Fasteners, according to certain non-limiting embodiments of thisenclosure, may be selected from screws, bolts, clamps, pins, rivets, andany other fasteners known now or heretofore to a person skilled in theart suitable for securing a cutting insert to a tool holder. Possiblematerials of construction for fasteners include, for example, steels,stainless steels, titanium alloys, and any other materials known now orheretofore by a person skilled in the art to have suitable mechanicalproperties and corrosion resistance for use in securing a cutting insertto a tool holder. In addition, the fastener must have a configurationand must comprise one or more materials suitable for directing coolant(which may have corrosive properties) toward the cutting edge in actionof a cutting insert.

The present disclosure has been written with reference to variousexemplary, illustrative, and non-limiting embodiments. However, it willbe recognized by persons having ordinary skill in the art that varioussubstitutions, modifications, or combinations of any of the disclosedembodiments (or portions thereof) may be made without departing from thescope of the invention as defined solely by the claims. Thus, it iscontemplated and understood that the present disclosure embracesadditional embodiments not expressly set forth herein. Such embodimentsmay be obtained, for example, by combining and/or modifying any of thedisclosed steps, ingredients, constituents, components, elements,features, aspects, and the like, of the embodiments described herein.Thus, the present disclosure is not limited by the description of thevarious exemplary, illustrative, and non-limiting embodiments, butrather solely by the claims. In this manner, it will be understood thatthe claims may be amended during prosecution of the present patentapplication to add features to the claimed invention as variouslydescribed herein.

We claim:
 1. A cutting tool comprising: a tool holder comprising acoolant port adapted to fluidly communicate with a coolant source; acutting insert comprising a cutting edge and a fastener bore extendingthrough the cutting insert; and a fastener comprising a shaft portionadapted to extend through the fastener bore to fasten the cutting insertto the tool holder, and a groove extending along the shaft portion,wherein the groove forms a portion of a coolant flow channel, andwherein the coolant flow channel is adapted to direct coolant from thecoolant port, along the coolant flow channel and through the fastenerbore, and toward the cutting edge.
 2. The cutting tool of claim 1,wherein the cutting insert forms a portion of the coolant flow channel.3. The cutting tool of claim 1, wherein the fastener further comprises ahead portion positioned outside the fastener bore.
 4. The cutting toolof claim 3, wherein the head portion further comprises a guide face, andwherein the guide face is angularly oriented toward the cutting edge. 5.The cutting tool of claim 1, wherein the fastener bore comprises acylindrical passage.
 6. The cutting tool of claim 5, wherein thecylindrical passage comprises an inner circumference and the shaftportion comprises an outer circumference, wherein the groove extendsradially inward on the shaft portion from the outer circumference, andwherein the outer circumference and the inner circumference form a sealadjacent to the groove.
 7. A cutting insert assembly for use with a toolholder, wherein the cutting insert assembly comprises: an insert bodycomprising: a cutting edge; and a fastener bore extending through theinsert body; and a fastener positioned at least partially through thefastener bore and adapted to fasten the insert body relative to the toolholder, wherein the fastener comprises an recess adapted to directcoolant along the fastener bore and toward the cutting edge.
 8. Thecutting insert assembly of claim 7, wherein the fastener furthercomprises a coolant flow guide.
 9. The cutting insert assembly of claim7, wherein the fastener bore comprises an inner perimeter, wherein thefastener comprises an outer perimeter, and wherein the recess extendsradially inward from the outer perimeter.
 10. The cutting insertassembly of claim 9, wherein regions of the inner perimeter abut theouter perimeter.
 11. A cutting tool, comprising: a holder comprising acoolant port adapted to fluidly communicate with a coolant source; acutting insert comprising a fastener bore; and a fastener, wherein atleast a portion of the fastener extends through the fastener bore andcomprises a coolant channel adapted to channel coolant from the coolantport through the cutting insert.
 12. The cutting tool of claim 11,wherein the coolant channel comprises a recess extending radially inwardfrom an outer perimeter of the fastener.
 13. The cutting tool of claim12, wherein the outer perimeter abuts the cutting insert adjacent to thecoolant channel.
 14. The cutting tool of claim 11, wherein the fastenerfurther comprises a coolant guide adapted to direct coolant toward acutting edge of the cutting insert.
 15. The cutting tool of claim 14,wherein the fastener further comprises a head, and wherein the coolantguide comprises an angled face of the head.
 16. The cutting tool ofclaim 11, wherein the fastener bore comprises a cylindrical bore throughthe cutting insert.
 17. The cutting tool of claim 11, wherein thefastener bore defines a uniform diameter.
 18. A cutting insert assemblyfor use with a tool holder, the cutting insert assembly comprising: acutting insert body comprising: a cutting edge; and a fastener boreextending through the cutting insert body; a fastener adapted to fastenthe cutting insert body to the tool holder, wherein the fastenercomprises a shaft portion positioned at least partially through thefastener bore, and wherein the shaft portion comprises an outercircumference that forms a seal at regions of the outer circumference,between the fastener and the cutting insert body; and a coolant flowchannel provided along the fastener bore, wherein the coolant flowchannel is defined from the outer circumference of the fastener and intothe shaft portion, and wherein the coolant flow channel is adapted todirect coolant through the cutting insert body and toward the cuttingedge.
 19. The cutting insert assembly of claim 18, wherein the fastenerfurther comprises a head portion positioned outside the fastener bore.20. The cutting insert assembly of claim 19, wherein the head portioncomprises a guide face, and wherein the guide face is angularly orientedtoward the cutting edge.
 21. The cutting insert assembly of claim 18,wherein the insert forms a portion of the coolant flow channel.
 22. Acutting tool, comprising: a tool holder comprising a coolant port influid communication with a coolant source; a cutting insert positionablein a plurality of orientations relative to the tool holder, wherein theplurality of orientations comprises a first orientation, and wherein thecutting insert comprises a plurality of cutting edges, wherein theplurality of cutting edges comprises an first cutting edge portion thatis positioned to cut a workpiece when the cutting insert is in the firstorientation, and a fastener bore through the cutting insert; and afastener adapted to extend through the fastener bore and secure thecutting insert relative to the tool holder wherein the cutting toolcomprises a plurality of channels, and wherein the plurality of channelscomprises a single active channel in fluid communication with thecoolant port when the cutting insert is in the first orientation,wherein the active channel is defined intermediate the fastener and thecutting insert, and wherein the active channel is structured to directcoolant from the coolant port toward the first cutting edge portion. 23.The tool of claim 22, wherein the fastener further comprises a headportion positioned outside the fastener bore.
 24. The tool of claim 23,wherein the head portion further comprises a guide face, and wherein theguide face is angularly oriented toward the first cutting edge portionwhen the cutting insert is positioned in the first orientation.
 25. Thetool of claim 22, wherein the fastener further comprises a coolant flowguide.
 26. The tool of claim 25, wherein the coolant flow guidecomprises an axial recess.
 27. The tool of claim 22, wherein thefastener bore comprises a cylindrical passage, wherein the fastenercomprises an outer perimeter, wherein regions of the outer perimeter arepositioned against the insert within the cylindrical passage.
 28. Thetool of claim 27, wherein the active channel extends inwardly from theouter perimeter of the fastener.